Barack Obama nominates Hillary Clinton as Secretary of State

US President-Elect Barack Obama has nominated his erstwhile political foe Hillary Clinton as his secretary of state, and has confirmed his other key advisers.

"In this uncertain world, the time has come for a new beginning – a new dawn of American leadership to overcome the challenges of the 21st century, and to seize the opportunities embedded in those challenges," Mr Obama said on Monday.

The president-elect also announced that Defence Secretary Robert Gates will stay on in his post.

Fifty days before he is sworn in as president, Mr Obama selected former Nato supreme Commander James Jones as national security adviser.

The picks are the latest collection of political power players to join a formative cabinet replete with experience on the world stage and in Washington's political jungle.

Mr Obama unveiled his team at a Chicago press conference after several weeks of frenzied speculation sparked by his offer to Mrs Clinton to become the top US diplomat.

Mr Obama and Vice President-elect Joseph Biden named their team just days after the Mumbai assaults handed them a fresh South Asia crisis to add to the plethora of US national security challenges.

Mr Obama completed the top layers of his national security team with Arizona Governor Janet Napolitano as Homeland Security chief.

Pending Senate confirmation, long-time Obama foreign policy aide Susan Rice was formally named as US ambassador to the United Nations.

And Mr Obama officially unveiled Eric Holder as his pick for attorney general, several weeks after his nomination leaked out in Washington.

Last week, Mr Obama drafted a string of intellectual heavyweights into his economic team, reassuring markets traumatised by the raging financial crisis.

Selecting Mr Gates, who is respected across the political aisle in Washington for his performance since taking over from Donald Rumsfeld two years ago, would allow Mr Obama to honour his pledge to name at least one Republican cabinet member.